diff --git a/changelog b/changelog
index 965fce8..e7bbee8 100644
--- a/changelog
+++ b/changelog
@@ -1,3 +1,4 @@
+20080823 tpd src/algebra/aggcat.spad UnaryRecursiveAggregate API examples
 20080822 tpd src/input/Makefile add linalg, overload regression tests
 20080822 tpd src/input/linalg.input recovered
 20080822 tpd src/input/overload.input recovered
diff --git a/src/algebra/aggcat.spad.pamphlet b/src/algebra/aggcat.spad.pamphlet
index 0719be4..69b8371 100644
--- a/src/algebra/aggcat.spad.pamphlet
+++ b/src/algebra/aggcat.spad.pamphlet
@@ -1,3 +1,4 @@
+
 \documentclass{article}
 \usepackage{axiom}
 \begin{document}
@@ -1618,90 +1619,196 @@ DoublyLinkedAggregate(S:Type): Category == RecursiveAggregate S with
 ++ Since these aggregates are recursive aggregates, they may be cyclic.
 UnaryRecursiveAggregate(S:Type): Category == RecursiveAggregate S with
    concat: (%,%) -> %
-      ++ concat(u,v) returns an aggregate w consisting of the elements of u
-      ++ followed by the elements of v.
-      ++ Note: \axiom{v = rest(w,#a)}.
+     ++ concat(u,v) returns an aggregate w consisting of the elements of u
+     ++ followed by the elements of v.
+     ++ Note: \axiom{v = rest(w,#a)}.
+     ++
+     ++E m:=[1,2,3]      
+     ++E concat(5,m)
+
    concat: (S,%) -> %
-      ++ concat(x,u) returns aggregate consisting of x followed by
-      ++ the elements of u.
-      ++ Note: if \axiom{v = concat(x,u)} then \axiom{x = first v}
-      ++ and \axiom{u = rest v}.
+     ++ concat(x,u) returns aggregate consisting of x followed by
+     ++ the elements of u.
+     ++ Note: if \axiom{v = concat(x,u)} then \axiom{x = first v}
+     ++ and \axiom{u = rest v}.
+     ++
+     ++E m:=[1,2,3]      
+     ++E concat(m,m)
+
    first: % -> S
-      ++ first(u) returns the first element of u
-      ++ (equivalently, the value at the current node).
+     ++ first(u) returns the first element of u
+     ++ (equivalently, the value at the current node).
+     ++
+     ++E m:=[1,2,3]      
+     ++E first(m)
+
    elt: (%,"first") -> S
-      ++ elt(u,"first") (also written: \axiom{u . first}) is equivalent to first u.
+     ++ elt(u,"first") (also written: \axiom{u . first}) is 
+     ++equivalent to first u.
+
    first: (%,NonNegativeInteger) -> %
-      ++ first(u,n) returns a copy of the first n (\axiom{n >= 0}) elements of u.
+     ++ first(u,n) returns a copy of the first n 
+     ++ (\axiom{n >= 0}) elements of u.
+     ++
+     ++E m:=[1,2,3]      
+     ++E first(m,2)
+
    rest: % -> %
-      ++ rest(u) returns an aggregate consisting of all but the first
-      ++ element of u
-      ++ (equivalently, the next node of u).
+     ++ rest(u) returns an aggregate consisting of all but the first
+     ++ element of u
+     ++ (equivalently, the next node of u).
+     ++
+     ++E m:=[1,2,3]      
+     ++E rest m
+
    elt: (%,"rest") -> %
-      ++ elt(%,"rest") (also written: \axiom{u.rest}) is
-      ++ equivalent to \axiom{rest u}.
+     ++ elt(%,"rest") (also written: \axiom{u.rest}) is
+     ++ equivalent to \axiom{rest u}.
+
    rest: (%,NonNegativeInteger) -> %
-      ++ rest(u,n) returns the \axiom{n}th (n >= 0) node of u.
-      ++ Note: \axiom{rest(u,0) = u}.
+     ++ rest(u,n) returns the \axiom{n}th (n >= 0) node of u.
+     ++ Note: \axiom{rest(u,0) = u}.
+     ++
+     ++E m:=[1,2,3]      
+     ++E rest(m,2)
+
    last: % -> S
-      ++ last(u) resturn the last element of u.
-      ++ Note: for lists, \axiom{last(u) = u . (maxIndex u) = u . (# u - 1)}.
+     ++ last(u) resturn the last element of u.
+     ++ Note: for lists, \axiom{last(u) = u . (maxIndex u) = u . (# u - 1)}.
+     ++
+     ++E m:=[1,2,3]      
+     ++E last m
+
    elt: (%,"last") -> S
-      ++ elt(u,"last") (also written: \axiom{u . last}) is equivalent to last u.
+     ++ elt(u,"last") (also written: \axiom{u . last}) is equivalent to last u.
+
    last: (%,NonNegativeInteger) -> %
-      ++ last(u,n) returns a copy of the last n (\axiom{n >= 0}) nodes of u.
-      ++ Note: \axiom{last(u,n)} is a list of n elements.
+     ++ last(u,n) returns a copy of the last n (\axiom{n >= 0}) nodes of u.
+     ++ Note: \axiom{last(u,n)} is a list of n elements.
+     ++
+     ++E m:=[1,2,3]      
+     ++E last(m,2)
+
    tail: % -> %
-      ++ tail(u) returns the last node of u.
-      ++ Note: if u is \axiom{shallowlyMutable},
-      ++ \axiom{setrest(tail(u),v) = concat(u,v)}.
+     ++ tail(u) returns the last node of u.
+     ++ Note: if u is \axiom{shallowlyMutable},
+     ++ \axiom{setrest(tail(u),v) = concat(u,v)}.
+     ++
+     ++E m:=[1,2,3]      
+     ++E last(m,2)
+
    second: % -> S
-      ++ second(u) returns the second element of u.
-      ++ Note: \axiom{second(u) = first(rest(u))}.
+     ++ second(u) returns the second element of u.
+     ++ Note: \axiom{second(u) = first(rest(u))}.
+     ++
+     ++E m:=[1,2,3]      
+     ++E second m
+
    third: % -> S
-      ++ third(u) returns the third element of u.
-      ++ Note: \axiom{third(u) = first(rest(rest(u)))}.
+     ++ third(u) returns the third element of u.
+     ++ Note: \axiom{third(u) = first(rest(rest(u)))}.
+     ++
+     ++E m:=[1,2,3]      
+     ++E third m
+
    cycleEntry: % -> %
-      ++ cycleEntry(u) returns the head of a top-level cycle contained in
-      ++ aggregate u, or \axiom{empty()} if none exists.
+     ++ cycleEntry(u) returns the head of a top-level cycle contained in
+     ++ aggregate u, or \axiom{empty()} if none exists.
+     ++
+     ++E m:=[1,2,3]      
+     ++E concat!(m,tail(m))
+     ++E cycleEntry m
+
    cycleLength: % -> NonNegativeInteger
-      ++ cycleLength(u) returns the length of a top-level cycle
-      ++ contained  in aggregate u, or 0 is u has no such cycle.
+     ++ cycleLength(u) returns the length of a top-level cycle
+     ++ contained  in aggregate u, or 0 is u has no such cycle.
+     ++
+     ++E m:=[1,2,3]      
+     ++E concat!(m,tail(m))
+     ++E cycleLength m
+
    cycleTail: % -> %
-      ++ cycleTail(u) returns the last node in the cycle, or
-      ++ empty if none exists.
+     ++ cycleTail(u) returns the last node in the cycle, or
+     ++ empty if none exists.
+     ++
+     ++E m:=[1,2,3]      
+     ++E concat!(m,tail(m))
+     ++E cycleTail m
+
    if % has shallowlyMutable then
       concat_!: (%,%) -> %
 	++ concat!(u,v) destructively concatenates v to the end of u.
 	++ Note: \axiom{concat!(u,v) = setlast_!(u,v)}.
+        ++
+        ++E m:=[1,2,3]
+        ++E n:=[4,5,6]
+        ++E concat!(m,n)
+
       concat_!: (%,S) -> %
 	++ concat!(u,x) destructively adds element x to the end of u.
 	++ Note: \axiom{concat!(a,x) = setlast!(a,[x])}.
+        ++
+        ++E m:=[1,2,3]      
+        ++E concat!(m,5)
+
       cycleSplit_!: % -> %
 	++ cycleSplit!(u) splits the aggregate by dropping off the cycle.
 	++ The value returned is the cycle entry, or nil if none exists.
-	++ For example, if \axiom{w = concat(u,v)} is the cyclic list where v is
+	++ If \axiom{w = concat(u,v)} is the cyclic list where v is
 	++ the head of the cycle, \axiom{cycleSplit!(w)} will drop v off w thus
 	++ destructively changing w to u, and returning v.
+        ++
+        ++E m:=[1,2,3]
+        ++E concat!(m,m)
+        ++E n:=[4,5,6]
+        ++E p:=concat(n,m)
+        ++E q:=cycleSplit! p
+        ++E p
+        ++E q
+
       setfirst_!: (%,S) -> S
 	++ setfirst!(u,x) destructively changes the first element of a to x.
+        ++ 
+        ++E m:=[1,2,3]
+        ++E setfirst!(m,4)
+        ++E m
+
       setelt: (%,"first",S) -> S
 	++ setelt(u,"first",x) (also written: \axiom{u.first := x}) is
 	++ equivalent to \axiom{setfirst!(u,x)}.
+
       setrest_!: (%,%) -> %
 	++ setrest!(u,v) destructively changes the rest of u to v.
+        ++
+        ++E m:=[1,2,3]
+        ++E setrest!(m,[4,5,6])
+        ++E m
+
       setelt: (%,"rest",%) -> %
-	++ setelt(u,"rest",v) (also written: \axiom{u.rest := v}) is equivalent to
-	++ \axiom{setrest!(u,v)}.
+	++ setelt(u,"rest",v) (also written: \axiom{u.rest := v}) 
+	++ is equivalent to \axiom{setrest!(u,v)}.
+
       setlast_!: (%,S) -> S
 	++ setlast!(u,x) destructively changes the last element of u to x.
+        ++
+        ++E m:=[1,2,3]
+        ++E setlast!(m,4)
+        ++E m
+
       setelt: (%,"last",S) -> S
 	++ setelt(u,"last",x) (also written: \axiom{u.last := b})
 	++ is equivalent to \axiom{setlast!(u,v)}.
+
       split_!: (%,Integer) -> %
-	 ++ split!(u,n) splits u into two aggregates: \axiom{v = rest(u,n)}
-	 ++ and \axiom{w = first(u,n)}, returning \axiom{v}.
-	 ++ Note: afterwards \axiom{rest(u,n)} returns \axiom{empty()}.
+	++ split!(u,n) splits u into two aggregates: \axiom{v = rest(u,n)}
+	++ and \axiom{w = first(u,n)}, returning \axiom{v}.
+	++ Note: afterwards \axiom{rest(u,n)} returns \axiom{empty()}.
+        ++
+        ++E m:=[1,2,3,4]
+        ++E n:=split!(m,2)
+        ++E m
+        ++E n
+
  add
   cycleMax ==> 1000